Improvement in steam-engines



UNITED STATES CHARLES LEVEY, OF TORONTO, CANADA.

l IMPROVEMENT` IN STEAM-ENGINES.

Specification forming part of Letters Patent No. 118,463, dated August 29, 1871.

To all whom it may concern:

Be it known that I, CHARLES LEvEv, of the city of Toronto, in the county of York, Province of Ontario, Canada, have invented certain new and useful Improvements in Steam-Engines, of which the following is a specification:

The invention consists in forming the main portion of the engine in two parts, viz.: the frame, valve-seat, and one-h alf the cylinder' in one piece, and the steam-chest and other' half-cylinder also in one piece, the two fitted together lengthwise, making the complete frame, steam-chest, and cylinder, all to be hereinafter fully explained.

In the drawing, Figure 1 is a perspective View of the steam-chest, cylinder, and frame. Fig. 2 is a plan of the engine with the upper half of the cylinder, Sto., removed. Fig. 3 is an end crosssection of the cylinder, steam-chest, valves, Src. Fig. 4 is a sectional side elevation of the balanced valve. Fig. 5 is a bottom, and Fig. 6 is a top View ofthe disk and ring of the valve. Figs. 7 and 8 are views` oftwo varieties of the variable eccentric. The cylinder is made in two or more pieces, A A, being divided lengthwise, and the lower half A, valve-seat B, and guide-bearings being cast in one piece with the frame C. The upper half A and steam-chest D are also cast in one piece. This makes the top of the frame on a line with the center of the cylinder, thus saving much expensive labor, as the top of the frame, guide-bearings, valve-seat, joints, .&c., can be planed, &c., by one chuckingi The working parts of the cylinder, and its face, and the valveseat are chilled instead of being cored out in the usual manner, thus making the surfaces where the most friction occurs almost as hard as steel, which is an important improvement over the ordinary manner of casting cylinders, 85e. The exhaustports a a and steam-ports b b are made in the cylinder-face or valve-seat, (as plainly shown in Fig. 2,) and are connected with the cylinder' by the usual passages c c. The cylinder is made double, (see Fig. 3,) leaving an exhaust steampassage, d, between the parts, thus making la complete steam-jacket. The slide-valves are of a peculiar and improved form, and belong to that class denominated balanced valves. The bottoms of them are made in the usual manner, with two lugs, g g', projecting up from the center of each valve, and are provided with dlsks, h, h', which are fastened securely to the top of the lugs g g.

These disks have a groove or gutter, i', running around the entire circumference on the un'der side7 its object to be presently explained. j is an annular rin which eneircles the disk L, and slides freely but closely over its periphery. ois a spring of sufficient strength to bear or hold up the ring j and keep itin contact with the cover when the steam is sluit off. Vhen the engine is at work the pressure ot' the steam on the lower edge of the ring j causes it to press tightly against the cover 7a ofthe steam-chest, thus forming a steampacked joint around the air-holes m in. The pressure of the steam in the annular groove i, shown in the under side of the disk IL, causes its periphery to expand against the inside ofthe ring j, thus steam-packing the joint between the disk and ring, the metal on the outside of the groove being made very thin to allow the steam to bend it easily. The disk h does not come quite up to the cover k, and the air-holes m m in the cover of the steam-chest are to allow the atmosphere to enter on top of the disks and thus balance the atmosphere on the exhaust side of the valve. The disks li are of the same area asI the surface of the valve, thus causing' the valves to work in equilibrium and removing a large amount of friction. One or more of these balancing-disks may be employed as required, to suit the various forms of valves. Figs. 7 and S are two f'orms of the variable eccentric, that shown in Figs. 7 and 2 being a variation of Fig. S. This (Fig. 8) consists of the'usual eccentric disk and rod k, with an oblong slot, F, instead of the usual round hole, so that it will slide over a square or fiat piece, M, formed or fastened on the shaft P, so that the eccentric, by means of the slot F, can be made to assume a more or less eccentric or a concentric position on the shaft. The position of the eccentric can be changed by means ofthe disk H, provided with a pin, [,which fits an eccentric slot, p, and by revolving on the shaft moves the eccentric by the pin on the slot p. Fig. 7 is a variation of this form, and consists of the usual cam E, provided with a slot, F, through which the shaft P passes. Upon the face of the cam E are two dovetailed projections or slides, n a', which work ina similarly-shaped groove in adisk, o, which serve the same purpose as the square piece m in Fig. 8, which is secured to the shaft P, (see Fig. 2,) so that the throw of the eccentric is made greater or lesser by moving it upon the shaft by means of the slot F, and the dovetailed grooves and lugs cause it to revolve with the shaft. To more easily adjust it I provide it with another disk, H, as in Fig. S, having two eccentric slots, 19, in the disk instead of one in the cam-face, as in Fig. 8; and with two pi.ns,I I,in the fac-e of the cam running in the slots, so that by turning the disk H the eccentric is moved toward or from the center by means of the slot F, and the throw of the eccentric graduated to suit the supply'of the steam to the engine. Balls, 80e., may be attached to the outer disk H and thus forni a perfect governor, which will regulate the size of the eccentric to the speed ofthe en gine and pressure of the steam.

To recapitulate, the variable eccentric which works the valve is provided with a slotted instead of the usual round hole, as in Figs. 7 and 8, so that it can be made to slide over the square on the plate on one disk, or dovetailiii the other disk, as in Fig. 7 one of which or some similar device will be keyed to the shaft so that the eccentric can be made to assume a more or less eccentric or concentric position on said shaft. The

position of the eccentric can be changed by a lever moved by hand when it is required for reversing or stopping the engine, or by the ordinary governor when required for regulating the speed.

I claiml. Constructing the steam-cylinder A A', bedplate B, steam-jacket, steam-chest, and cylinderface or valve-seat in two parts; the bed-plate C, lower half of cylinder A, and steam-jacket el, steam-ports, and exhaust a b, and cylinder-face or valve-seat B in one part; the upper half of cylinder A', and upper half of steam-jacket d', and the steam-chest D in the other part, as hereinbefore set forth, and for the purpose specified.

2. The method of constructing the bed-plate, upper and lower halves of steam-cylinder, cylinder-face or valve-seat, guide-bearings, pillowblock bearings, and steam-chest in such a manner that the whole of the parts above named, together with the top of the bed-plate, can be planed or finished at one chucking77 and thus be perfectly in line.

3. The steam-cylinder A A divided in the direction of its length, and planing or finishing the same in that direction, as hereinbefore specified.

I n witness whereof I have hereunto signed my naine in the presence of two subscribing witnesses.

GHAS. LEVEY.

Witnesses:

J. R. BRAKE, ALBERT HAIGHT. 

